Metal deactivator composition of low freezing properties



July 10, 1962 Grams I Grams 0f Solvent J. P. HATCHER ET AL 3,043,783

METAL DEACTIVATOR COMPOSITION OF LOW FREEZING PROPERTIES Filed March 31,1960 Jazz/yam W A rToR/vEYs 3,043,783 METAL DEACTIVATOR COMPOSITION 6FLOW I FREEZING PROPERTEES Julian P. Hatcher, La Grange, George E.Atherton, Argo, and William L. Cox, Mount Prospect, IlL, assignors toUniversal Oil Products Company, Des Plaines, 1th, a corporation ofDelaware Filed Mar. 31, 1960, Ser. No. 18,918

2 Claims. (Cl. 252-403) This is a continuation-in-part of applicationSerial N 0. 717,847, filed February 27, 1958, now abandoned, which inturn is a continuation-in-part of application Serial N 0. 602,496, filedAugust 7, 1956, now abandoned, and relates to a novel metal deactivatorcomposition of low freezing properties. i a

A major disadvantage to certain metal deactivators being marketed at thepresent time isthat the metal deactivators are not sufiiciently solublein the commonly used solvents at low temperatures. the winter months theactive component of the metal deactivator precipitates out of solutionand freezes in the drums, tanks or other receptacles, and the metaldeactivator cannot be pumped or used in the normal manner. It isapparent that this is a serious disadvantage and entails additionalexpense and time on the part of the user in order to warm the solutionto a suitable temperature at which it can be pumped.

It now has been found that a mixed solvent solution containing criticalproportions of the components will provide a solution which will remainliquid at these low temperatures As will beshoWn by the appendedexamples, the novel mixed solvent of the present invention results in asolution which will remain liquid at lower temperatures than isobtainable by using either of these solvent components separately.Accordingly, the novel solution of the present invention can be pumpedand used as required without the. necessity of heating and otherhandling before satisfactory use of the metal deactivator.

The novel metal deactivator composition of the present invention isemployedto deactivate the catalytic effect of metals in any substratecontaining such metals. These metals catalyze oxidation of organicsubstances. The metal deactivator composition thus is useful to preventsuch deterioration of motor fuels, fats, edible oils, lubricating oils,diesel oils, fuel oils, etc. The present invention is particularlyapplicable to the stabilization of olefincontaining motor fuels such ascracked or polymer gasoline, or mixtures of these with straight runand/or natural gasolines.

One method of refining gasoline is the copper sweetening process, inwhich process the gasoline is treated with a copper-containing reagent.As a-resu1t of this treatment, the sweetenedlgasoline usually containsrelatively small amounts of copper compounds which catalyze oxidationreactions. In addition, gasolines come in contact with various metals inthe course of refining, storing and shipping operations, and the metalsmay catalyze the oxidation reactions. In some cases, this also mayresult in the gasoline containing minor amounts of such metals ascopper, iron, cobalt, nickel, chromium, lead, etc., which have adetrimental effect on the stability of the gasoline. In addition togasoline, the other-organic compounds hereinbefore set forth also becomecontaminated with metallic constituents during the course of refining,storing Accordingly, during 3,043,783 Patented July 10,. 1962 2 andshipping operations and, accordingly, are deleteriously affected by themetallic constituents.

A particularly effective metal deactivator comprises the condensationproduct of an ortho-hydroxy aromatic aldehyde with an aliphatic amine.For example, disalicylalpropylenediamine is prepared by the condensationof 2 mols of salicylaldehyde with 1 mol of propylenediamine. For ease inhandling and use, the disalicylalpropylenediamine is prepared as asolution in an aromatic solvent. While this metal deactivatorcomposition is very effective, it suffers from the disadvantage ofhaving too high a freezing point. For example, at temperatures normallyencountered in the winter months, disalicylalpropylenediamineprecipitates out of solution. This interferes with the easy use of thedeactivator composition and necessitates heating of the composition inorder to dissolve the disalicylalp'ropylenediamine in the solvent. Thisdisadvantage is avoided by the novel metal deactivator composition ofthe present invention.

In one embodiment the present invention relates to a metal deactivatorcomposition comprising the condensation product of an ortho-hydroxyaromatic aldehyde with an aliphatic amine dissolved in a solvent mixtureof from about 5% to about 25 by weight of an alcohol and from about 95%to about 75% by weight of an aromatic hydrocarbon.

In a specific embodiment the present invention relates to a metaldeactivator composition comprising from about 30% to about 80% and moreparticularly from about 40% to about by Weight of the condensation prod-7 net of salicylaldehyde with propylenediamine dissolved in from about20% to about and more particularly from about 40% to about 60% by weightof a solvent mixture containing from about 5% to about 25% by weight ofmethanol and from about to about by weight of toluene In anotherembodiment the present invention relates to an organic substancecontaining a metal which normally catalyzes oxidative deterioration andadditionally containing a small amount of the metal deactivatorcomposition set forth herein.

As hereinbefore set forth, the metal deactivator com- 7 positionincludes the condensation product of an orthohydroxy aromatic aldehydewith an aliphatic amine. Any suitable ortho-hydroxy aromatic aldehydemay be utilized and preferably comprises salicylaldehyde ororthovanillin and mixtures thereof. Other ortho-hydroxy aromaticaldehydes include 2-hydroxy-6-methyl-benzalde- .hyde,2-hydroxy-3-methoxy-benzaldehyde, 2-hydroxy-4- used will be selectedwith reference to its effectiveness, availability and cost.

When either two or more ortho-hydroxy aromatic aldehydes and/or two ormore aliphatic amines are used in the preparation of the metaldeactivator, the metal deactivator will comprise a mixture of thecondensation products. This mixture is referred to herein as activeingredient, in contrast to the solvent which is not active to effectdeactivation of metals.

The condensation of ortho-hydroxy aromatic aldehyde and aliphatic amineis effected in any suitable manner. The reaction is effected readily atroom temperature and generally is etfected in the presence of an organicsolvent in order to facilitate subsequent removal of the water formed inthe reaction. Water and solvent are removed in any' suitable manner,including draining, distillation, etc.

As hereinbefore set forth, the condensation product is prepared as asolution in a particular mixed solvent. Also, as hereinbefore set forth,the mixed solvent of the present invention results in a solution whichremains liquid at lower temperatures than solutions containing eitherone of the solvents alone. The preferred mixed solvent of the presentinvention comprises from about 5% to about by weight of methanol andfrom about 75% to about 95% by weight of toluene.

While the mixture of methanol and toluene is particularly preferred, insome cases other aromatic hydrocarbons and other alcohols may be used.Other aromatic hydrocarbons include benzene, xylene, cumene, etc. ormixtures thereof and/or with toluene. Other alcohols include ethanol,l-propanol, 2-propanol, l-butanol, 2- butanol and, in some cases,pentanol, hexanol, heptanol, octanol, etc., or mixtures of these and/ ormixtures thereof with methanol. However, it is understood that thediiferent aromatic hydrocarbons and alcohols are not necessarilyequivalent.

As hereinbefore set forth, the mixed solvent of the present inventionprovides a metal deactivator composition of improved solidificationproperties. These improved properties result in a solution which willremain liquid at lower temperatures than solutions prepared from eitherof these solvent components alone. These advantages prevail at anytemperature. Accordingly, a solution containing a given concentration ofactive ingredient will remain liquid at a lower temperature than asolution containing the same concentration of active ingredient butprepared in toluene alone or in methanol alone. This is illustrated inthe accompanying drawing which will be discussed in detail withreference to the appended examples.

As above set forth, the concentration of active ingredient in thesolution will depend upon the temperature of the geographical areas inwhich the metal deactivator solution is to be used. For example, inareas of extremely low temperatures, the concentration of activeingredient will be within the range of from about to about 50% by weightof the solution. In intermediate temperature areas, the concentration ofactive ingredient may range from to 60%. In areas of moderatetemperatures or, in cases where the solution is kept indoors or heatedprior to use, the solution may contain from about 60% to about 80% byweight of active ingredient. Thus, it will be seen that the advantagesof the novel composition of the present invention prevail at a widerange of temperatures and that the percent of active ingredient in thesolution will vary accordingly. However, at any given temperature, thenovel solution of the present invention olfers advantages over the useof either of these solvent components alone. Thus, any general teachingsin the prior art that aromatic hydrocarbons or alcohols may be usedobviously do not teach the important concept and will not result in theimproved deactivator solutions of the present invention.

The metal deactivator functions in a manner entirely distinct from thatof a gum inhibitor which normally is incorporated in gasoline. The guminhibitor does not suppress the catalytic action of the metal to anyconsiderable extent and, on the other hand, the metal deactivator doesnot suppress gum formation per se to any considerable extent, but servesprimarily to deactivate the metal constituents and thereby to destroythe catalytic effect thereof to enhance oxidative reactions.

Any suitable gum inhibitor may be employed along With the metaldeactivator composition of the present invention. These gum inhibitorsare well known and generally include various phenols, amines,aminophenols, as well as fractions of wood tar, oil, etc. A particularlysuitable gum inhibitor comprises N,N-di-secondary-'butyl-pphenylenediamine. Another particularly suitable gum inhibitor comprises a mixtureof a major proportion of N-butyl-p-aminophenol and a minor proportion ofN,N'- di-butyl-p-phenylene diarnine. It is understood that the guminhibitor may be prepared as a mixed product with the metal deactivator,and the mixed solution marketed as a single commodity.

The gum inhibitor usually is incorporated in gasoline in a concentrationof from about 0.0005 to about 1% by weight, and the metal deactivatorgenerally is incorporated in the gasoline in a smaller concentration,which may range from about 0.000l% to about 0.5% by weight (based onactive constituent). When used in other substrates, it is understoodthat lower or higher concentrations may be used which generally will bebelow about 1% by 'weight of the substrate.

The following examples are introduced to illustrate further the noveltyand utility of the present invention but not with the intention ofunduly limiting the same.

EXAMPLE I Table l Solvent Solubility of disalicylalpropylenedlamine,g./100 Percent Percent g. of solvent Toluene Methanol From the data inthe above table, it will be noted that the use of methanol inconcentrations above about 25% resulted in lower solubility ofdisalicylalpropylenediamine. On the other hand, it will be noted thatuse of the mixed methanol-toluene solvent, the former in a concentrationof from about 5% to about 25% by weight of the solvent, resulted in aconsiderable increase in the solubility of disalicylalpropylenediamine.

EXAMPLE 11 Another series of solubility runs made using thedisalicylalpropylenediamine and toluene-methanol solvent 5 described inExample I. This series of runs was made at 5 F., and the results thereofare reported in the following table:

Table II Solvent Solubility or disalicylalpropylenediamine, g./100Percent Percent g. of solvent Toluene Methanol Here again, it will benoted that the same general results are obtained at 5 F. as compared tothe runs made at 36 F. as reported in Example I. Also, it will be notedthat the solubility of disalicylalpropylenediamine,

v even in the. mixed solvent, is considerably lower than at 36 F.However, the solubility at this .low temperature is the most importantfor the following reasons: (1) The freezing difficulties are encounteredat the low temperature and, in order to be satisfactorily used, themetal deactivator composition must remain fluid at the low temperature.(2) A solution which is fluid at the low temperature will be fluid at ahigher temperature and therefore will not present any freezing problemsat the higher temperature.

EXAMPLE III Another series of solubility runs was made using thedisalicylalpropylenediamine described in Example I and toluene-methanolsolvent. This series of runs was made at 70 F. 'and the results thereofare reported in the following table:

Table III Solvent Solubility of disalicylalpropylenediamine, g./l00Percent Percent g. of solvent Toluene Methanol Here again, it will benoted that the same general results are obtained at 70 F. as wereobtained at 36 F.

and at 5 1?. as reported in Examples I and 11'. Thus,

metal deactivator solution will be used. However", re-

ga'rdless' of the specific concentration of active ingredient in themixed solvent, the solution will remain liquid at a lower temperaturethan otherwise obtainable when using either of the solvent componentsalone.

EXAMPLE IV The metal deactivator of this example comprised 50% by weightof active ingredient, 45% by weight of toluene and 5% by weight ofmethanol. The acitve ingredient contains 95 by weight of thecondensation product of 2 mols salicylaldehyde with l'mole ofpropylenediamine (1,2-diarninopropane). solution remains stable attemperatures above 5 F.

EXAMPLE V The metal deactivator of this example comprised 41.5% byweight of active ingredient, the active ingredient being the same as theone described in Example IV. The solvent consisted of 58.5% by weight ofthe total solution and comprised 9% by weight of methanol and 91 byweight of toluene.

EXAMPLE VI The active metal deaotivattor component of this example wasprepared by the condensation of 2 mols of salicylaldehyde with 1 mol ofpropylenediamine (1,2- diaminopropane). A solution comprising 60% byweight of the active metal deaetivator, 36% by Weight of toluene and 4%by weight of methanol is prepared.

The above solution is utilized in the stabilization of a thermallycracked gasoline. The unstabi-lized gasoline has an Induction Period ofminutes. Upon the addition of 0.1% by weight of an antioxidantcomprising N,N-di-secondary-bntyl-p-phenylene diamine, the InductionPeriod of the gasoline is increased to 1050 minutes. However, upon theaddition of 1 part per million (1 mg.

7 per liter) of copper, in the form of copper oleate, the

the solvent mixtures in which the methanol comprises L from about 5% toabout 25% by weight and the toluene comprises from about 75% to about95% by weight results in considerably higher solubility ofdis-alicylalpropylenedi-amine. Another advantage to the present invention is a reduction in shipping costs because of the lower amount ofsolvent included in the composition. However, as hereinbefore set forth,in other instances it is desired to prepare solutions containing a lowerconcentration of active ingredient. The particular proportions of activeingredient and solvent therefore will vary, depending upon the ambientconditions 'at which the Induction Period of the gasoline drops to 55minutes. Upon the addition of 7 parts per million of the copperdeactivator solution described above, the Induction Period of the.gasoline is raised to 995 minutes. It will be noted that the metaldeactivator solution of the present invention serves to offset thedeleterious effect of the copper and produces a final gasoline of highstability.

EXAMPLE VII The metal deactivator of this example comprised di-SaIicyial-IE-diaminobntane and was prepared by the condensation of 2mols of sailicylaldehyde with 1 mol of 3,3-diarninobntane. A compositionof 44% by weight of disalicylal-1,3-di-aminobutane in toluene has, amelting point of about 178 F. However, the melting point is considerablydecreased by utilizing a mixed solvent comprising 90% toluene and 10%methanol.

EXAMPLE VIII A metal deactivator composition is prepared by dissolvingthe mixed condensation product of 2 ortho hydroxy aromatic aldehydeswith an al-kylene polyarnine in a mixed solvent comprising 90% by weightof xylene and 10% by weight of isopropyl alcohol.

EXAMPLE IX The metal deactivator composition of this example comprises40% by Weight of salicylaldehydepropylenediamine in a mixed solventcomprising 85% by weight of benzene and 15% by weight of secondary butylalcohol.

EXAMPLE X The metal deactivator solution described in Example V1 is usedfor the stabilization of lard. The lard has a '7 test comprises bubblingair through a sample of the lard and periodically determining theperoxide number. The results are reported as the number of hoursrequired to reach a peroxide number of 20.

In order to determine the efiect of metal, a 3" strip of 18 gauge copperwire is added to a sample of the lard. The stability of the lard isreduced from four hours to one hour in the presence of the copper.However, upon the addition of the metal deactivator solution describedabove, the stability of the lard is increased to four hours.

Here again, it will be noted that the metal deactivator solution of thepresent invention serves to effectively olfset the deleterious effect ofthe copper.

We claim as our invention:

1. A solution of from about 30% to about 80% by weight ofdisalicylalpropylenediamine in from about 8 to about 70% by weight of asolvent mixture of from about 5% to about by weight of methanol and fromabout 75% to about 95% by weight of toluene.

2. A solution of from about 40% to about by weight ofdisalicylalpropylenediamine in from about 40% to about 60% by weight ofa solvent mixture of from about 5% to about 25% by weight of methanoland from about to about by weight of toluene.

References Cited in the file of this patent UNITED STATES PATENTS2,282,513 Downing et al. May 12, 1942 2,284,267 Downing et al. May 26,1942 2,573,779 Walters Nov. 6, 1951 2,579,692 Neudeck Dec. 25, 1951

1. A SOLUTION OF FROM ABOUT 30% TO ABOUT 80% BY WEIGHT OFDISALICYLALPROPYLENEDIAMINE IN FROM ABOUT 20% TO ABOUT 70% BY WEIGHT OFA SOLVENT MIXTURE OF FROM ABOUT 5% TO ABOUT 25% BY WEIGHT OF METHANOLAND FROM ABOUT 75% TO ABOUT 95% BY WEIGHT OF TOLUENE.